An electronic oscillator is an electronic circuit that produces a repetitive oscillating electronic signal, such as a sine wave or a square wave. Oscillators may be used to convert a direct current (DC) from a DC power supply to an alternating current (AC). They are widely used in many electronic devices. Some examples of signals generated by oscillators include signals broadcast by radio and television transmitters, clock signals that regulate computers and quartz clocks, and the sounds produced by electronic beepers and video games.